locks: create posix-to-flock helper functions

Factor out a bit of messy code by creating posix-to-flock counterparts
to the existing flock-to-posix helper functions.

Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>

1 files changed, 36 insertions, 25 deletions

diff --git a/fs/locks.c b/fs/locks.c
index 1a00b8bc65ed..957775ba6468 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1611,6 +1611,38 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
         return error;
 }
 
+static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
+{
+        flock->l_pid = fl->fl_pid;
+#if BITS_PER_LONG == 32
+        /*
+         * Make sure we can represent the posix lock via
+         * legacy 32bit flock.
+         */
+        if (fl->fl_start > OFFT_OFFSET_MAX)
+                return -EOVERFLOW;
+        if (fl->fl_end != OFFSET_MAX && fl->fl_end > OFFT_OFFSET_MAX)
+                return -EOVERFLOW;
+#endif
+        flock->l_start = fl->fl_start;
+        flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
+                fl->fl_end - fl->fl_start + 1;
+        flock->l_whence = 0;
+        return 0;
+}
+
+#if BITS_PER_LONG == 32
+static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
+{
+        flock->l_pid = fl->fl_pid;
+        flock->l_start = fl->fl_start;
+        flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
+                fl->fl_end - fl->fl_start + 1;
+        flock->l_whence = 0;
+        flock->l_type = fl->fl_type;
+}
+#endif
+
 /* Report the first existing lock that would conflict with l.
  * This implements the F_GETLK command of fcntl().
  */
@@ -1645,24 +1677,9 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
  
         flock.l_type = F_UNLCK;
         if (fl != NULL) {
-                flock.l_pid = fl->fl_pid;
-#if BITS_PER_LONG == 32
-                /*
-                 * Make sure we can represent the posix lock via
-                 * legacy 32bit flock.
-                 */
-                error = -EOVERFLOW;
-                if (fl->fl_start > OFFT_OFFSET_MAX)
-                        goto out;
-                if ((fl->fl_end != OFFSET_MAX)
-                    && (fl->fl_end > OFFT_OFFSET_MAX))
+                error = posix_lock_to_flock(&flock, fl);
+                if (error)
                         goto out;
-#endif
-                flock.l_start = fl->fl_start;
-                flock.l_len = fl->fl_end == OFFSET_MAX ? 0 :
-                        fl->fl_end - fl->fl_start + 1;
-                flock.l_whence = 0;
-                flock.l_type = fl->fl_type;
         }
         error = -EFAULT;
         if (!copy_to_user(l, &flock, sizeof(flock)))
@@ -1798,14 +1815,8 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
         }
  
         flock.l_type = F_UNLCK;
-        if (fl != NULL) {
-                flock.l_pid = fl->fl_pid;
-                flock.l_start = fl->fl_start;
-                flock.l_len = fl->fl_end == OFFSET_MAX ? 0 :
-                        fl->fl_end - fl->fl_start + 1;
-                flock.l_whence = 0;
-                flock.l_type = fl->fl_type;
-        }
+        if (fl != NULL)
+                posix_lock_to_flock64(&flock, fl);
         error = -EFAULT;
         if (!copy_to_user(l, &flock, sizeof(flock)))
                 error = 0;